Automatic self-loading hoist



March 29,1927.

W. E. HOWLETT AUTOMATIC SELF LQADING HOIST 2 Sheets-Shee,t 1

Filed April 21, 1926 March 29, 1921. 1,622,589

r W. E. HOWLETT AUTOMATIC SELF LOADING HOIST Filed ril 21 1 Patented Mar. 29, 1927.

UNITED STATES- WILLIAM E. HOWLETT, OF MOLIINE, ILLINOIS.

AUTOMATIC SELF-LOADING HOIST.

Application filed April 21, 1926. Serial No. 103,422.

The invention relates to an automatic sel'tloading hoist.

It relates particularly to certain improve-- ments in the hoist shown in my prior Patent No. 1,592,602. July 13, 1926.

Automatic hoists of this type are generally used for hoisting coal. They include an elevating tower having a loading bin near its base, a hoisting bucket that is automatically lowered to and raised "from said bin, and a door for closing the opening from the bin through which the bucket is loaded. hen the bucket is lowered. the door is opened to permit the coal to pass into the bucket and as the bucket is raised the door moves to close the opening to prevent coal from flowing into the tower while thebucket is being raised to the top of the tower and dumped.

In my prior hoist the door was moved to closed position by counterweights, the door being held open while the bucket was lowered by the bucket itself which engaged projections on the door. Although these weights would close the door they had to be made quite heavy in order to push the door through the coal. The. present invention provides an improved means for positivelypushing the door through the coal toward closed position as the bucket is raised, after which it may be moved to final position and held there by weights.

The bucket in my prior hoist was also provided with a pivoted plate near its loading edge which was automatically turned from an inclined to a vertical position as the bucket was raised to increase the height of' the loading side of the bucket to preventmaterial from dribbling of? the leading edge as the bucket was raised; After this plate was turned to vertical position the coal fell in behind it and it could not be returned to its inclined posit-ion inside the bucket until present invention provides an improved safety apparatus for accomplishing the same result in a' more efliclent manner.

One of the objects of the invention is to, provide an improved ineans for positively closing the door in an automatic self-loading hoist asthe hoisting bucket is raised.

Another object is to provide an improved means for operating the plate which prevents coal from dribbling from the bucket as it rises.

Other objects and advantages of the invention will appear from the specification and drawings.

An embodiment of the invention is shown in the drawings in which:

Fig. 1 is a side elevation of the hoist showing the bucket in lowered position in full) lines and in partly raised position in dot and dash lines.

Fig. 2 is a Vertical cross-section on the line 22 of Fig. 3.

Fig. 3 is a vertical cross-section on the line 33 of Fig. 1.

Fig. 4 is a horizontal cross-section line 44 of Fig. 1.

The lower portion of the elevating tower 1 is provided with a bin 2, having an open-- ing into the tower in which is located a choker plate 3 (Fig. 2) for regulating the flow of material through the opening. A lip 4 extends forward into the tower at the bottom of the opening over which coal may flow into the hoisting bucket whose path is spaced from the front of the tower. Metal on the side pieces 5 are positioned at the sides of this lip to prevent coal from falling over its edges and to form an enclosure for catching coal that may be thrown from the loading side of the bucket as it rises.

The opening from the bin into the tower is normally closedby a metal door 10 which is urged to closed position by counterweights 11 connected by cables 12 passing over pulley 13 to lugs 14 on the door, as illustrated in Fig. 3. The counter-weights are heavy enough to close the door if it is not seriously obstructed, but, on account of the possibility of the door becoming jammed in open position thereby allowing coal to flow into the tower while the bucket is raised, it is desirable to have a positive means for closing the door. Such a means is provided which is actuated by the hoist-ing bucket.

The hoisting bucket 15 is raised and lowered in the tower through a cable 16 con n-ected at one end to a bail 17 on the bucket and at its other end to a suitable automatic hoisting apparatus not illustrated. When the bucket is lowered it engages projections 18 011 the door 10 and positively moves it to the open position shown in Fig. 2 to permit coal to flow into the bucket. hen the bucket is raised the door is released to permit the counter-weights 11 to act, but in addition to this the bucket itself positively raises the door.

The door 10 carries arms pivoted at 21 and having rollers 22 on their outer ends which travel on guides 23 supported by the side pieces 5 in the tower. The inner ends of these levers are cam shaped for engage ment by studs 24 on the hoisting bucket. As the bucket is raised these studs engage the ends of the levers and, since the levers cannot turn on their pivots because of the engagement of the rollers 22 with the guides 23, the bucket is effectively connected to the door and positively raises the door with it during which movement the rollers 22 travel on the guides 23. The guides 23 terminate in curved port-ions 25 and, when the rollers 22 reach these curved portions, the arms turn on their pivots to the dotted line position shown in Fig. 1 which permits the studs 24 on the hoisting bucket to pass the levers and the bucket is thus released from the door. The curved portions of the guides are located so that the bucket is not released from the door until after the door has been forced up through the coal and is in a position such that the counter-weights can easily move it to its final position. The guides thus act as a controlling means for determining the action of the raising arms or devices 20. The levers 20 are balanced to remain in their tilted position when the door is closed, their position being determined by the engagement of projections 26 on them with the lugs 14 to which the cables 12 are connected. As the bucket is lowered it engages the projections 18 on the door and lowers it, causing the rollers 22 to engage the guides 25-23 and return the levers 20 to position to be acted upon by the studs Qt when the bucket is again raised. During the descent of the bucket, the studs 24 pass the ends of the tilted arms 20 before these arms are returned by engagement with the curved ends 25 of the guides 23.

In this manner the door is positively moved during the initial and hardest .part of its travel, and the bucket is automatically released from it after this diflicult portion has been passed. The construction permits a minimum number of simple parts to be used. These may be made very rugged which is necessary in a device of this kind.

The hoisting bucket is provided with a plate 30 shown in Fig. 2 fixed to a; shaft 31, pivoted near the loading edge of the bucket. Connected to the outer ends of this shaft are arms or dogs 32 which occupy the position illustrated in Fig. 1 when the bucket is low ered. As the bucket is raised the plate 30 is turned to the position shown in dotted lines at the upper part of Fig. 1. This movement of the plate throws out a portion of the coal at the forward side of the bucket and increases the height of the leading edge of the bucket so as to prevent coal from dribbling from the bucket as it is raised. The coal that is thrown out falls down in the space between the bucket and the tower and into the bin. My prior hoist was provided with a plate of this kind and the present invention relates especially to an improved means for operating it. Such a means must return the plate as the bucket is lowered, must prevent breaking of the parts it the bucket is lowered without its contents having been unloaded, and it must be very simple, rugged, and dependable.

Pivoted on the side plates 5 are passby pawls 33 which are weighted so as to normally occupy the position in which one of them is shown in Fig. 1 in contact with a stud 34 on the side plate. As the bucket rises the dogs 32 on the ends of shaft 31 engage the ends of the pawls 33 and, since these pawls cannot turn counter clock-wise by reason of their contact with the studs 34:, the arms 32 are rotated counter clockwise and the plate 30 is turned from the position illustrated in Fig. 2 to that shown in dotted lines at the top of Fig. 1. This throws a portion of the coal out of the bucket and raises the height of the loading side to prevent coal from dribbling out.

As the bucket is lowered the arms 32 again strike the pawls 33 and, since the latter are weighted at their rear ends and there is considerable friction of the parts, the resistance that they offer is sutticient to return the plate 30 to its position illustrated in Fig. 2, such return being aided by the weight of the plate itself, which, when it once starts to turn, tends to move the rest of the way by gravity. If the bucket should be accidentally lowered before it is unloaded there would be coal behind the plate 30 so that it could not be returned to its position shown in Fig. 2. In such event the arms 32 engage the pawls 33 but, instead of the pawls turning the plate 30, the pawls themselves are turned and the arms 32 simply pass by the pawls. In this manner the parts may pass each other without breaking in the event of accidental lowering of the bucket Without it having been emptied.

It is to be understood that the structure shown is for purposes of illustration and that variations may be made in it without departing from the spirit and scope of the invention as defined by the claims.

I claim:

1. The combination in an automatic selfloading hoist of a receptacle having an opening through which the material to be hoisted may pass, a closure for said opening, a hoisting bucket adapted to be loweredntoand.

to be raised from said opening, raising devices carried. by said closure, means carried by the hoisting bucket.forengaging said raising devices as the bucket is raisedto move them toward disengaging position, and means for preventing said raising devices from moving to disengaging position until said closure reaches a substantially closed position.

2. The combination in an automatic selfloading hoist of a receptacle having an opening through which material to be hoisted may pass, a closure for said opening, a hoisting bucket adapted to be lowered to and be raised from said opening, raising devices carried by said closure, means carried by the hoisting bucket for engaging said raising devices as the bucket is raised. and tends ing to move them to disengaging position, and means for preventing said raising devices from being moved to disengaging position until said closure reaches a substantially closed position, said last named means having provislonsrfor returning the raising.

arms carried by said closure, projections.

on the hoisting bucket engaging the ends of the arms, guides engaging the opposite ends of the arms to prevent said arms from turning when engaged by the projections on the buckets, said guides terminating to release the arms to permit them to turn to permit the projections on the bucket to pass the arms.

l. The combination in an automatic, selfloading hoist of a receptacle having an opening through which material to be hoisted may pass, a closure for said opening, a hoisting bucket adapted to be lowered to and to be raised from said opening, arms pivoted to said. door, projections carried by said bucket engaging the ends of said arms, and rollers carried by the other ends of said arms engaging stationary guides, said guides having curved ends to permit the arms to turn to permit the projections on the hoisting bucket to pass the arms after the bucket has been raised a predetermined height.

5. The combination in an automatic selfloading hoist of a receptacle having an opening through which material to be hoisted may pass, a closure for said opening, a hoisting bucket adapted to be lowered to and to be raised from said opening, means for moving the closure to an open position as the bucket is lowered, raising devices carried said closure for engagement by engag- .out of the path of said engaging means,

and controlling means for movingsaid raising devices,.as the bucket is lowered, to a position to be engaged by the engaging means as the bucket is raised and for holding them in said position until the closure is moved to a substantially closed position.

6. The combination in an automatic, selfloading hoist .ot a hoisting bucket. adapted to be lowered to and to be raised from an opening in a loading bin, a plate pivoted adjacent the loading edge of the door and extending inside the bucket, pivoted pawls adjacent the path of the bucket, stops, for limiting the movement of said pawls in one direction, and means connected with said plate adapted to engage said pawls as the bucket is raised to thereby turn the plate to vertical position, said means also engaging the plate as the bucket is lowered to return the plate to its position inside the bucket.

7. The combination in an automatic, seltloading hoist of a hoisting bucket adapted to be lowered to and to be raised from an opening in a loading bin, a plate pivoted adjacent the leading edge of the bucket and extending inside. thereof, pivoted pawls adjacent the path of the bucket, said pawls being weighted to normally engage limiting stops which prevent their movement in one direction, and means connected with said plate for engaging saidpawls as the bucket is raised to movethem in the direction of the stops, said pawls serving to actuate said means to turn said plate to vertical position as the bucket is raised, said pawls also serving to return said plate to its position inside the bucket as the bucket is lowered and to permit said means connected with the plate to pass the pawls in the event the plate is prevented from being returned to its position inside the bucket.

8. The combination in an automatic, selfloading hoist of a hoisting bucket adapted to be lowered to and to be raised from a loading bin, a plate pivoted adjacent the loading edge of said bucket and projecting inside thereott, passby pawls pivoted adjacent the path of movement of the bucket, and means connected to said plate for engaging said pass-by pawls to turn the plate to vertical position as the bucket is raised, and to lower it to its position inside the bucket as the bucket is lowered, said pawls also permitting the means to pass the pass-by pawls in the event the plate is prevented from returning.

9. The combination in an automatic, selfloading hoist of a hoisting bucket adapted to be lowered to and to be raised from an opening in a loading bin, a plate pivoted adjacent the loading side of said bucket and normally extending inside thereof, actuating devices positioned adjacent the path of the bucket, and means connected to said plate and engaged by said actuating devices as the bucket moves past them for automatically turning the plate to vertical position as the bucket is raised and for returning said plate to its position inside the bucket as the bucket is lowered, said actuating devices including portions which move to permit the means carried by the plate to pass them in the event the plate cannot be returned to its position inside the bucket.

10. The combination in an automatic, selfloading hoist, of a hoisting bucket adapted to be lowered to and to be raised from an opening in a loading bin, a shaft journaled adjacent the loading edge of the bucket and carrying a plate extending inside thereof, arms connected to said shaft at the sides of the bucket, and pivoted pass-by pawls in the path of movement of said arms, said pawls serving to actuate said arms to turn the shaft and the plate when the bucket is being raised and when it is being lowered, and permitting the arms to pass the pawls when the bucket is lowered when the plate cannot be moved.

11. The combination in an automatic selfloading hoist of a hoisting bucket adapted to be lowered to and to be raised from an opening in a loading bin, means carried by the bucket adjacent the loading side thereof for automatically increasing the height of the side of the bucket as it is raised, actuating devices positioned adjacent the path of the bucket, and connections for said first named means positioned so as to be engaged by said actuating devices as the bucket moves past them for automatically actuating said means to increase the height of the side of the bucket as it is raised and for returning said means to normal position as the bucket is lowered, said actuating devices including portions which move to permit the connections to the height increasing means to pass them in the event said means is prevented from returning to its normal position as the bucket is lowered.

12. The combination in an automatic selfloading hoist of a hoisting bucket adapted to be lowered to and to be raised from an opening in a loading bin, means carried by the bucket adjacent the loading side thereof for automatically unloading a portion of the contents of the bucket as the bucket is raised, actuating devices positioned adjacent the path of the bucket, connections to said automatic unloading means positioned so as to be engaged by said actuating devices as the bucket moves past them as it is raised to automatically unload a portion of the material in the bucket and to automatically return said unloading means to normal position as the bucket is lowered, said actuating devices including portions which permit the connections to pass them in the event the unloding means cannot be returned to normal position as the bucket is lowered.

In testimony whereof, I have subscribed my name.

WILLIAM E. HOVVLE' T. 

